The present invention relates to trays for serving food, and more particularly to food serving trays for short term storage of food in zones of elevated temperature and zones of reduced temperature.
Mass serving of food requires storage of hot food materials, e.g. meat and cooked vegetables, as well as food of reduced temperature, e.g. ice cream, butter and the like. The requirement for temperature differential between the various food materials has created many difficulties in the past. One method for dealing with the problem has been to serve first the hot food materials and subsequently serve the low temperature foods. It is desirable, of course, to minimize the serving steps by providing both the hot food as well as the cold food in the same food storage tray.
Illustrative food serving trays providing zones for maintaining temperature differential between various food materials are U.S. Pat. No. 3,122,265 (Innis), U.S. Pat. RE. No. 30,962 (Bridges) and U.S. Pat. No. 3,754,640 (Bridges). Such patents disclose the concept of a heat insulating tray having a plurality of zones, each of which is adapted for receipt of a food container such as a plate, cup saucer or the like. The trays disclosed in such prior patents are stackable and the lower surface of one tray mates with the upper surface of the next lower tray, thus providing for enclosure of the various temperature zones. Such trays serve adequately to maintain the desired temperature differentials so long as the trays are maintained in a stacked relationship. However, once the trays are separated, the hot food, for example, may quickly cool and become less than satisfactory to the palate.
The present invention overcomes such problem by providing a first tray member suitable for stacking one upon another. The present invention further includes a second member which serves to close a zone containing food at elevated temperatures. The second member is adapted to lockingly engage the tray upon which it rests as well as engaging the tray next above so long as the trays are in the stacked position. The second member serves to maintain the elevated temperature of the hot food until the person receiving the food removes the cover.